Three different types of operating tables are typically used in hospitals, namely stationary operating tables, movable operating tables and mobile operating tables. Stationary operating tables have an operating table column permanently fixed to the floor of the operating room, wherein normally they do not comprise an operating table base and energy is supplied to them via fixedly installed cables.
Movable operating tables have an operating table column base which is connected to the operating table column and which has no rollers and no transport device and stands on the floor of the operating room at least during a surgical operation. The movable operating tables are liftable and movable by transport carriages. Such a system which comprises a movable operating table and a transport carriage is also referred to as a mobile operating table system,
The operating table column bases of mobile operating tables have rollers for moving the operating table so that they are movable without further auxiliary devices. In the case of mobile operating tables, electric traction drives, including soft start and safety brake function, can be used in order to move the mobile operating table by the electric traction drive.
The energy supply of the movable operating tables and the mobile operating tables can be provided via accumulators which are integrated in the operating table, in the operating table column base or in the operating table column.
Both in the case of stationary operating tables and in the case of movable operating tables and mobile operating tables, components which are adjustable by an electric motor can be provided, such as an operating table column which is length-adjustable by an electric motor for height variation of a patient support surface arranged on the operating table column, an operating table column head which is adjustable about two orthogonal axes for variation of tilt and swing of the patient support surface connected to the operating table column head, and/or components of the patient support surface that can be adjusted by an electric motor.
In particular in the case of operating tables which are supplied with energy via accumulators, it is appropriate to provide energy saving functions and to deactivate sensors, actuators and control functions when for a preset amount of time no control function has been activated by an input via a control element or no otherwise-initiated control function has been activated. During long surgical operations, the position of the patient is often maintained over long periods of time so that during these periods of time an energy saving function can be activated. If through such an energy saving function sensor units are also deactivated (which themselves have a relevant energy consumption and/or via which a control unit for evaluating the sensor signals of the sensor unit has a relevant energy consumption), a problem may occur in which the adjustment position of the component changes due to an external force (for example when a defect in a further component, such as a defect in the motor brake occurs). In particular, a height-adjustable operating table column can lower itself by the weight of the patient support surface and/or of the patient. If this happens during a surgical operation, then there is the possibility that a physician may be impeded in performing the surgical operation.
From document DE 199 55 116 A1, a control unit for controlling the drives of a patient support surface is known, in which a patient support surface is removable from an operating table column and comprises components adjustable by an electric motor, said control unit comprising an energy supply, a control and a control device. The control device is integrated in a transport carriage for the transport of the operating table support surface.
From document DE 10 2007 062 200 A1, an operating table having a plurality of components adjustable by control elements is known. The state and/or the change of state of at least some of the control elements is detected by sensors, the signals generated by the sensors being fed to a processing device.
From document DE 10 2005 054 223 A1, a device for adjusting an operating table is known which has an operating table column on which an adjustable patient support surface is arranged. The device comprises a control device for inputting adjustment commands for adjusting components of the operating table. The adjustment commands can be transmitted from the control device directly to the adjustable support surface.
From document DE 10 2005 053 754 A1, a device for adjusting the patient support surface of an operating table is known, which comprises several segments that are adjustable relative to each other. At least some of the adjustable segments are connected to actuators which are controllable for adjusting the associated segments. The actuators are electric motors. The input device has a device for inputting body-part-related adjustment commands which are associated with the adjustment of the position of a body part or a body portion of a patient lying on the patient support surface.